US11730608B2 - Monoblock expandable interbody implant - Google Patents

Abstract

A unibody implant movable between an expanded position and a contracted position is disclosed. The unibody implant may include a unitary expandable body defined by an inferior portion and a superior portion that are connected together. In various embodiments, a set screw may be rotatably supported by the body and configured to move a plug having a first inclined surface facing the distal side. In various embodiments, the set screw may be movable in the longitudinal direction towards the distal side upon rotation of the set screw along the rotation axis, for example. In various embodiments, movement of the set screw urges the plug against the superior portion thereby expanding a vertical distance between the superior and inferior sides of the body. In some embodiments, the plug may include a stabilizing element configured to transfer compressive forces between the superior portion and inferior portion.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application incorporates the entire disclosure of U.S. patent application Ser. No. 17/246,968, titled UNIBODY DUAL EXPANDING INTERBODY IMPLANT, filed May 3, 2021; and U.S. patent application Ser. No. 17/332,284, titled RHOMBOID SHAPED IMPLANTS, filed May 27, 2021 by reference.

FIELD

The present technology is generally related to a unibody expanding interbody implant for use in a medical procedure related to the spine. In some embodiments, disclosed implants may be used in an anterior cervical discectomy and fusion (ACDF) procedure although other uses in other areas of the spine or between two bones are also contemplated.

BACKGROUND

Mechanically operated interbody implants may be used to align and/or realign a patient's spine during a medical procedure. Conventional implants designed for the Thoracic and Lumbar region of the spine often include top and bottom endplates and a mechanical means to separate the top and bottom endplates. The mechanical mechanisms to separate the top and bottom endplates are often cumbersome and require a large footprint that is often unsuitable, for example, for ACDF type surgeries of the cervical portion of the spine.

SUMMARY

The techniques of this disclosure generally relate to a unibody implant that is independently expandable at a first side and a second side opposite the first side.

In one aspect, the present disclosure provides for a unibody implant movable between an expanded position and a contracted position, for example. The unibody implant may extend from a proximal side or end to a distal side or end in a longitudinal direction, extend from a first lateral side to a second lateral side in a lateral direction, and extend from a superior side to an inferior side in a vertical direction, for example. Here, the term longitudinal is used for purposes of defining the direction from the proximal end to the distal end and the term lateral direction is used to define the direction perpendicular to the longitudinal direction. In various embodiments, the unitary expandable body may be defined by an inferior portion, and a superior portion, and the inferior portion may be connected to the superior portion, for example. In various embodiments, a set screw or actuator screw may be rotatably supported by the body and rotatable in a clockwise direction and a counterclockwise direction around a rotation axis. In some embodiments, the rotation axis may extend parallel to the longitudinal direction and in other embodiments the rotation axis may extend in an off angle orientation to the longitudinal direction, for example. For example, the rotation axis may extend in a direction that is angled at about 0 degrees to about 25 degrees with respect to the longitudinal direction, for example. In various embodiments, a plug or wedge may be disposed adjacent to and may be in contact with the set screw, and the plug may further have a first inclined surface facing the distal side, for example. In various embodiments, the set screw may be referred to as an actuating screw and rotation thereof may cause the plug to move, e.g., the set screw may actuate motion of the plug and therefore be referred to as an actuating screw. In various embodiments, the superior portion may comprise a first inclined ramp disposed on an interior surface thereof and facing the first inclined surface of the plug, for example. In various embodiments, the set screw may be movable in the longitudinal direction towards the distal side or end upon rotation of the set screw along the rotation axis, for example. In various embodiments, movement of the set screw in the longitudinal direction towards the distal side urges the first inclined surface of the plug against the first inclined ramp thereby expanding a vertical distance of the body between the superior and inferior sides of the body adjacent the proximal side of the body.

In another aspect, the disclosure provides for a method for expanding and contracting a unibody implant. The method may include the step of providing a unibody implant. In various embodiments, the unibody implant may extend from a proximal side to a distal side in a longitudinal direction, extend from a first lateral side to a second lateral side in a lateral direction, and extend from a superior side to an inferior side in a vertical direction, for example. In various embodiments, the unitary expandable body may be defined by an inferior portion, and a superior portion, and the inferior portion may be connected to the superior portion, for example. In various embodiments, a set screw may be rotatably supported by the body and rotatable in a clockwise direction and a counterclockwise direction around a rotation axis. In some embodiments, the rotation axis may extend parallel to the longitudinal direction and in other embodiments the rotation axis may extend in an off angle orientation to the longitudinal direction, for example. In various embodiments, a plug may be disposed adjacent to and in contact with the set screw, and the plug may have a first inclined surface facing the distal side, for example. In various embodiments, the superior portion may comprise a first inclined ramp disposed on an interior surface thereof and facing the first inclined surface of the plug, for example. In various embodiments, the set screw may be movable in the longitudinal direction towards the distal side upon rotation of the set screw along the rotation axis, for example. In various embodiments, movement of the set screw in the longitudinal direction towards the distal side urges the first inclined surface of the plug against the first inclined ramp thereby expanding a vertical distance of the body between the superior and inferior sides of the body adjacent the proximal side of the body. The method may include the step of rotating the set screw such that it linearly translates from the proximal side towards the distal side and the step of pushing the plug, by the set screw, towards the distal side, for example. The method may further include the step of urging, by the plug, the first inclined ramp of the superior portion up and away from the inferior portion, for example.

The details of one or more aspects of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the techniques described in this disclosure will be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF DRAWINGS

FIG.1 is a front exploded parts view of an implant.

FIG.2 is a rear exploded parts view of an implant.

FIG.3 is a front perspective view of an implant.

FIG.4 is an alternate front perspective view of an implant.

FIG.5 is a side perspective view of an implant.

FIG.6 is an alternate side perspective view of an implant.

FIG.7 is a top down view of an implant.

FIG.8 is a side view of an implant in an expanded configuration.

FIG.9 is a side view of an implant in an expanded configuration.

FIG.10 is a cross section view of an implant in an expanded configuration.

FIG.11 is an enlarged view of section Z-Z ofFIG.10.

FIG.12 is a perspective cross section view of an implant in an expanded configuration with some components removed for ease of understanding.

FIG.13 is a reference drawing showing the human spine of which various disclosed implant embodiments may be installed in.

FIG.14 is a reference drawing showing various planes and reference directions of which the various disclosed implant embodiments may move in or act in with respect to a patient.

DETAILED DESCRIPTION

Embodiments of the present disclosure relate generally, for example, to spinal stabilization systems, and more particularly, to a unibody implant having a superior portion and an inferior portion that are connected and expandable and contactable by action of a set screw and a plug. Embodiments of the devices and methods are described below with reference to the Figures.

The following discussion omits or only briefly describes certain components, features and functionality related to medical implants, installation tools, and associated surgical techniques, which are apparent to those of ordinary skill in the art. It is noted that various embodiments are described in detail with reference to the drawings, in which like reference numerals represent like parts and assemblies throughout the several views, where possible. Reference to various embodiments does not limit the scope of the claims appended hereto because the embodiments are examples of the inventive concepts described herein. Additionally, any example(s) set forth in this specification are intended to be non-limiting and set forth some of the many possible embodiments applicable to the appended claims. Further, particular features described herein can be used in combination with other described features in each of the various possible combinations and permutations unless the context or other statements clearly indicate otherwise.

Terms such as “same,” “equal,” “planar,” “coplanar,” “parallel,” “perpendicular,” etc. as used herein are intended to encompass a meaning of exactly the same while also including variations that may occur, for example, due to manufacturing processes. The term “substantially” may be used herein to emphasize this meaning, particularly when the described embodiment has the same or nearly the same functionality or characteristic, unless the context or other statements clearly indicate otherwise.

Referring toFIGS.1-12 generally, variousspinal implant100 embodiments are disclosed. The components ofspinal implant100 can be fabricated from biologically acceptable materials suitable for medical applications, including metals, synthetic polymers, ceramics and bone material and/or their composites. For example, the components of spinal implant100, individually or collectively, can be fabricated from materials such as stainless steel alloys, commercially pure titanium, titanium alloys, Grade 5 titanium, super-elastic titanium alloys, cobalt-chrome alloys, superelastic metallic alloys (e.g., Nitinol, super elasto-plastic metals, such as GUM METAL®), ceramics and composites thereof such as calcium phosphate (e.g., SKELITE™), thermoplastics such as polyaryletherketone (PAEK) including polyetheretherketone (PEEK), polyetherketoneketone (PEKK) and polyetherketone (PEK), carbon-PEEK composites, PEEK-BaSO4 polymeric rubbers, polyethylene terephthalate (PET), fabric, silicone, polyurethane, silicone-polyurethane copolymers, polymeric rubbers, polyolefin rubbers, hydrogels, semi-rigid and rigid materials, elastomers, rubbers, thermoplastic elastomers, thermoset elastomers, elastomeric composites, rigid polymers including polyphenylene, polyamide, polyimide, polyetherimide, polyethylene, epoxy, bone material including autograft, allograft, xenograft or transgenic cortical and/or corticocancellous bone, and tissue growth or differentiation factors, partially resorbable materials, such as, for example, composites of metals and calcium-based ceramics, composites of PEEK and calcium based ceramics, composites of PEEK with resorbable polymers, totally resorbable materials, such as, for example, calcium based ceramics such as calcium phosphate, tri-calcium phosphate (TCP), hydroxyapatite (HA)-TCP, calcium sulfate, or other resorbable polymers such as polyaetide, polyglycolide, polytyrosine carbonate, polycaroplaetohe and their combinations.

Referring generally toFIGS.1-12 animplant100 is disclosed. Theimplant100 may be used for an ACDF surgery in the cervical area of the spine (seeFIG.13), and expand in various planes of a patient1 (seeFIG.14). However, other uses within the lumbar and/or thoracic area of the spine or between two bones or bone portions or within the void located in a bone are also contemplated. The present disclosure aims to reduce the complexity of mechanical mechanisms to cause distraction, lordosis, and/or kyphosis while increasing the available interior space of an implant by minimizing the size of the moving mechanism that causes distraction, lordosis, and/or kyphosis. At least one advantage of minimizing the size of the moving mechanism is that a relatively greater volume of a bone growth promoting material may be placed and/or injected inside of the implant for promoting fusion between adjacent vertebrae of a patient.

Implant100 may be referred to as a monoblock implant, monolithic implant unibody implant, and/or unitary implant in some embodiments. As used herein, the terms monolithic, unitary, and/or unibody shall have their ordinary technical meaning. For example, referring to a component that a person of ordinary skill in the art would consider being formed as a continuous single piece. However, it shall be understood that in various embodiments a continuous single piece may have respective portions that are connected to one another to form the continuous single piece.

Implant100 may include aninferior portion10 and asuperior portion20 that define the outside surfaces ofimplant100. It shall be understood that althoughimplant100 is described herein as being composed of aninferior portion10 and asuperior portion20 that these portions are securely connected to one another to form animplant100. For example, theinferior portion10 is connected to thesuperior portion20. In various embodiments, theimplant100 is expandable between a contracted position and an expanded position by movement of aset screw40 which acts against and pushes aplug50. In various embodiments, plug50 may also be referred to as a barrel and/or include a hollow center. In various embodiments, setscrew40 may be positioned anteriorly ofplug50 and rotation ofset screw40 may cause setscrew40 to advance and therefore pushplug50.

In various embodiments, theset screw40 may include a drive feature42 (may also be referred to as a drive end aperture) including a plurality of peaks and valleys disposed on an interior circumferential surface, and athread pattern44 disposed on an exterior circumferential surface. Drivefeature42 may extend through setscrew40 and, in the illustrated embodiment, drivefeature42 may resemble a hexalobular shaped aperture. However, other designs are contemplated, e.g., thedrive feature42 may resemble the geometry of the tip of a torx driver, hex driver, phillips driver, square head driver, polygonal driver, or any combination thereof. In various embodiments, arear surface46 ofset screw40 may be configured to directly contact and push against afront surface56 ofplug50. Various surgical tools may rotate setscrew40, for example the surgical tool200 disclosed in U.S. application Ser. No. 17/246,968, the entire contents of which are incorporated herein by reference. In the example embodiment,rear surface46 may have a relatively flat and/or substantially planar smooth surface surrounding the open aperture shape ofdrive feature42.

In the example embodiment, plug50 includes a base portion having a substantially cylindrical shape that transitions into an upper portion including a firstinclined surface52 and a stabilizingelement54. In the example embodiment, first inclinedsurface52 may extend between secondinclined surface53 and stabilizingfeature54, for example. In various embodiments, stabilizingfeature54 may be disposed on a superior portion ofplug50 and extend towards a proximal side ofimplant100 and/or an anterior side ofimplant100 depending on orientation. Stabilizingfeature54 may provide a bearing surface for providing a stabilizing function between theinferior portion10 andsuperior portion20, for example, which will be explained in further detail below. Additionally, first inclinedsurface52 may act against a corresponding inclined surface ofimplant100 to cause expansion ofimplant100, for example, which will be explained in further detail below. Similarly, secondinclined surface53 may act against a corresponding inclined surface ofimplant100, and/or act as a bearing surface for a corresponding portion ofimplant100 whenimplant100 is in an expanded configuration, for example, which will be explained in further detail below.

In various embodiments, theset screw40 may be rotatably engaged with a first threadedaperture16 of theinferior portion10 and the cylindrical base portion ofplug50 may be coaxially aligned withset screw40. For example, the cylindrical base portion may have a central point positioned approximately in a center of a circle defining, at least partly,front surface56 and the central point may be coaxially aligned with a central axis of rotation ofset screw40. However, it shall be understood that in other embodiments, such coaxial symmetry is not required as setscrew40 may contact and push againstsurface56 ofplug50 and therefore moveplug50 without being coaxially aligned. Additionally, in various embodiments plug50 may optionally be hollow and/or include an aperture coaxially aligned with the aperture ofdrive feature42, for example the cross section drawing ofFIG.11. In various embodiments, the threadedaperture16 may include a discontinuity at an upper end thereof for accommodating a corresponding portion ofsuperior portion20 and/or plug50. For example, a discontinuity in the uppermost surface ofinferior portion10 that may accommodate stabilizingfeature54. As will be explained in further detail below, an interior of thesuperior portion20 may include a first inclined ramp26 (seeFIG.8) of which the firstinclined surface52 ofplug50 may act against. For example, when rotating theset screw40 it may move forward and backward in a longitudinal direction within the first threadedaperture16 thereby pushingplug50 and urging the firstinclined surface52 ofplug50 against the firstinclined ramp26 to expand a vertical height of theimplant100.

FIGS.3 and4 are various perspective views of animplant100,FIGS.5 and6 are various perspective views of animplant100, andFIG.7 is a top down view ofimplant100. In the example embodiment,implant100 may extend in a longitudinal direction along axis A-A from aproximal side100pto adistal side100d. Those with skill in the art will appreciate thatproximal side100pmay be referred to as an anterior side anddistal side100dmay be referred to as a posterior side (and vice versa) depending on the orientation ofimplant100.Implant100 may extend in a lateral direction along axis B-B from a firstlateral side1001 to a secondlateral side1001, for example. Additionally,implant100 may include a superior side100s(top surface) and an inferior side1001 (bottom surface). In various embodiments, the superior side100smay be defined by thesuperior portion20 and theinferior side1001 may be defined by the inferior portion. Additionally, in various embodiments, a proximal end ofimplant100, for example a front vertical face ofimplant100 may be defined by a proximal surface ofinferior portion10 and a proximal surface ofsuperior portion20. For example, the front face ofimplant100 may be defined by both thesuperior portion20 andinferior portion10 as shown inFIG.3. It shall also be appreciated that a vertical spacing between thesuperior portion20 andinferior portion10 is expandable and contactable at theproximal side100pofimplant100 because thesuperior portion20 andinferior portion10 may not be rigidly connected at theproximal side100p. Additionally, in various embodiments a distal end ofimplant100, for example a rear surface ofimplant100, may be defined by a distal surface ofinferior portion10 and a distal surface ofsuperior portion20. For example, the rear face ofimplant100 may be defined by a region where both thesuperior portion20 andinferior portion10 are connected as shown inFIG.5. It shall also be appreciated that in various embodiments a vertical spacing between thesuperior portion20 and theinferior portion10, at thedistal side100dofimplant100, may not be adjustable and/or expandable because thesuperior portion20 andinferior portion10 are connected at thedistal side100d. For example still, thedistal side100dofimplant100 may act as a hinge and/or function as a hinge that undergoes an elastic deformation in an expanded configuration.

Referring toFIGS.3-7,implant100 may include a plurality of slottedapertures15a,15b,25a, and25bto facilitate fusion of adjacent vertebrae, for example. In various embodiments, slottedapertures15a,15b,25a, and25bmay be vertically aligned (see top down view ofFIG.7). Additionally, slottedapertures15a,15b,25a,25bmay be packed with a bone growth promoting material to facilitate a fusion process. In various embodiments,implant100 may include at least onebone screw aperture14,24. For example, theproximal side100pofimplant100 may include a firstbone screw aperture14 that extends through a vertical face ofinferior portion10 on theproximal side100pthrough a slottedaperture15bof theinferior side1001. In various embodiments, a portion of firstbone screw aperture14 may be formed in theinferior portion10 and/or have at least a portion thereof formed in theinferior surface1001. Additionally, the proximal side ofimplant100 may include a secondbone screw aperture24 that extends through a vertical face ofsuperior portion20 on theproximal side100pthrough a slottedaperture25aof the superior side100s. In various embodiments, a portion of secondbone screw aperture24 may be formed in thesuperior portion20 and/or have at a least a portion thereof formed in the superior surface100s. In various embodiments,bone screw apertures14,24 may be conically shaped and include various lip portions for retaining a head portion of a bone screw (not illustrated). In other embodiments,bone screw apertures14,24 may comprise an aperture maintaining substantially the same internal diameter, i.e., not tapering and/or conical. Additionally, in various embodimentsbone screw apertures14,24 may allow for some freedom of movement when installing a bonescrew therein by accommodating about +/−5 degrees in any direction relative to a target alignment, for example.

Implant100 may include at least one slit12,22 on eachlateral side1001. For example, afirst slit12 may take the form of a discontinuity extending in the longitudinal direction along the firstlateral surface1001 between theinferior portion10 and thesuperior portion20, for example. Thefirst slit12 may follow an undulating curved path and include a generally teardrop-shapedcutout11 proximate thedistal side100dto facilitate the expansion ofimplant100, for example. In various embodiments, and as illustrated, the undulating curved path offirst slit12 may be configured to facilitate an elastic deformation ofimplant100 by allowing enough of a void space for thesuperior portion20 to expand away from and relative to theinferior portion10, for example. Similarly, asecond slit22 may take the form of a discontinuity extending in the longitudinal direction along the secondlateral surface1001 between theinferior portion10 and thesuperior portion20, for example. Thesecond slit22 may include a generally teardrop-shapedcutout21 proximate thedistal side100d. In various embodiments, and as illustrated, the undulating curved path offirst slit12 may be configured to facilitate an elastic deformation ofimplant100 by allowing enough of a void space for thesuperior portion20 to expand away from and relative to theinferior portion10, for example.

In the example embodiment, first slit12 may extend along an undulating path alonglateral side1001 fromtear drop cutout11 towards a proximal side ofimplant100 and adjoin the proximal end ofimplant100 adjacent theinferior side1001. For example, first slit12 may extend fromtear drop cutout11 to the front face ofimplant100 and transition intoproximal slit23. Similarly, in the example embodiment second slit22 may extend along an undulating path alonglateral side1001 fromtear drop cutout21 to the front face ofimplant100 and adjoin the proximal end ofimplant100 adjacent the superior side100s. For example, second slit22 may extend fromtear drop cutout21 to the front face ofimplant100 and transition intoproximal slit23. Proximal slit23 may extend laterally along the proximal face ofimplant100 between the firstlateral end1001 and secondlateral end1001. In the example embodiment, proximal slit23 adjoins first slit12 adjacent theinferior side1001 ofimplant100 and adjoins second slit22 adjacent the superior side100s. In this way,implant100 may be disconnected and/or substantially disconnected on the firstlateral side1001, secondlateral side1001, andproximal side100pyet remain connected at thedistal side100d.

With reference toFIGS.8 and9, in various embodiments slits12,22 and teardrop-shapedcutouts11,21 may be featured on bothlateral sides1001 ofimplant100. Theslits12,22 and teardrop-shapedcutouts11,21 may be configured to facilitate the expansion and contraction ofimplant100 while theinferior portion10 andsuperior portion20 remain connected together at the distal side. For example, in an expanded configuration theslits12,22 and teardrop-shapedcutouts11,21 facilitate the pivoting of thesuperior portion20 relative to theinferior portion10 whileslit23 is enlarged (relative to a contracted configuration), for example. For example, by rotating setscrew40 such that it linearly translates from aproximal side100ptowards thedistal side100dand pushes plug50 from theproximal side100ptowards thedistal side100d. In movingplug50 towards thedistal side100dofimplant100 the firstinclined surface52 acts against the interior rampedsurface26 and pushes thesuperior portion20 up and away from theinferior portion10 while thedistal side100dofimplant100 is elastically deformed to allow the expansion. As seen best in the side profile ofFIG.9, firstinclined surface52 may act againstinclined ramp26 and secondinclined surface53 may act against and/or support a lower most surface ofinclined ramp26. In various embodiments, first inclinedsurface52 may be inclined by a greater degree than secondinclined surface53 and each may be inclined by a degree corresponding to the inclination ofinclined ramp26, for example.

Consistent with the above disclosure, actuation ofset screw40 and linear translation ofplug50 may cause a lordotic angle ofimplant100 to be adjusted and slits12,22,23, and teardrop cutouts11,21 may facilitate the elastic deformation ofimplant100 at thedistal side100d. As seen best inFIG.8, stabilizingfeature54 ofplug50 may prevent plug50 from rotating while also providing a bearing surface. For example, in various embodiments a bottom planar surface ofsupport feature54 may contact and/or slide across planarupper surface13 ofinferior portion10. In some embodiments, not illustrated, planarupper surface13 ofinferior portion10 may include a groove and/or recess for nesting and/or mating withsupport feature54.

FIG.10 illustrates a first cross section illustration through the center ofimplant100 in the longitudinal direction and/or through longitudinal axis A-A.FIG.11 illustrates an enlarged view of region Z-Z ofFIG.10. In the example illustration, it is shown that setscrew40 has pushedplug50 all the way to a maximum expanded configuration. For example, rotating setscrew40 may cause threads ofthread pattern44 to rotate within threadedaperture16 such thatset screw40 advances and pushes plug50. In the maximum expanded configuration, arear surface57 ofplug50 has abutted against astop feature18 ofinferior portion10. Stopfeature18 may be a surface or wall extending in a vertical direction, for example. Stopfeature18 may prevent the accidental over expansion ofimplant100 such that the only type of deformation that can occur is an elastic deformation, i.e., stopfeature18 may prevent the accidental occurrence of a plastic deformation be preventingplug50 from advancing too far. Additionally, it is shown thatsupport feature54 provides a bearing surface whereby forces fromsuperior portion20 may be transferred toinferior portion10 where an underside ofsupport feature54 contactsupper surface13 ofinferior portion10, for example. Additionally, rampedsurface26 may directly contact and bear down against firstinclined surface52 and/or secondinclined surface53, for example. In this way, compressive forces from adjacent vertebrae of a patient may be transferred between theinferior portion10 andsuperior portion20.

FIG.12 is a perspective cross section drawing withset screw40 and plug50 removed for ease of understanding of the internal geometry ofimplant100. In the example embodiment, threadedaperture16 may include a thread pattern that extends a portion of the distance between the proximal face ofimplant100 and stopfeature18. For example, the thread pattern of threadedaperture16 may terminate where the threads adjoin plugcavity19.Plug cavity19 may be a smooth arcuate surface corresponding to the outside diameter of the lower cylindrical portion ofplug50, for example.Plug cavity19 may be closed, at least partially, at a distal side thereof bystop feature18, as explained above. In various embodiments, and as illustrated inFIG.12, the geometry ofplug cavity19 may correspond to an arc of a circle having a radius that approximates the minimum diameter portion of the threads of threadedaperture16. For example, in a lateral cross section, plugcavity19 may be considered a portion of a circle having a diameter that corresponds to the minimum diameter of the thread pattern of threadedaperture16, for example. This arrangement may facilitate plug50 being able to pass through threadedaperture16 during assembly, for example.

Consistent with the disclosure herein, various embodiments ofimplant100 may include three distinct and unitary components, an implant body formed of asuperior portion20 andinferior portion10, aset screw40, and aplug50. Additionally, in various embodiments,implant100 may be pre-assembled. For example, theplug50 may be insert through threadedaperture16 and intoplug cavity19 and setscrew40 may be threadably engaged with threads of threadedaperture16 keepingplug50 within the interior ofimplant100. In some embodiments, not illustrated, a locking feature may be added to prevent theset screw40 from backing out. For example, a locking feature may include a pivoting arm disposed on the proximal face ofimplant100 that may rotate between a locked and unlocked position. In the locked position, the pivoting arm may block setscrew40 from backing out and in the unlocked position the pivoting arm may be pivoted away from threadedaperture16 such thatset screw40 may be removed. In other embodiments, a second set screw (not illustrated) may be installed behind thefirst set screw40 to cause jamming.

FIG.13 is a reference drawing showing the human spine of which various disclosed implant embodiments may be installed in.FIG.14 is a reference drawing showing various planes and reference directions of which the various disclosed implant embodiments may move in or act in. In operation, an end user such as a surgeon may placeimplant100 between two adjacent vertebrae. Thereafter, the surgeon may lordotically expandimplant100 by rotating setscrew40 thereby pushingplug50 distally and pushingsuperior portion20 away frominferior portion10. The surgeon may stop theset screw40 at any appropriate position and theimplant100 may be continuously adjustable between a non-expanded position and the maximum expanded position. In some embodiments,implant100 may have about 2 degrees to about 6 degrees of lordosis in a fully collapsed position and in other embodiments implant100 may have about 4 degrees of lordosis in the fully collapsed position. Similarly, in some embodiments implant100 may have about 12 degrees to about 18 degrees of lordosis in a fully expanded position and in other embodiments implant100 may have about 15 degrees or lordosis in the fully expanded position.

In various embodiments, it is contemplated that theimplant100 may be filled with a bone growth promoting material that is either solid or fluid and flowable. In at least one embodiment, a flowable bone growth promoting material may be injected through thehollow set screw40 and through a hollow embodiment ofplug50 such that the flowable graft material enters into the interior ofimplant100. For example, as described in detail in U.S. patent application Ser. No. 17/246,968, the entire contents of which are incorporated herein by reference.

It should be understood that various aspects disclosed herein may be combined in different combinations than the combinations specifically presented in the description and accompanying drawings. For example, features, functionality, and components from one embodiment may be combined with another embodiment and vice versa unless the context clearly indicates otherwise. Similarly, features, functionality, and components may be omitted unless the context clearly indicates otherwise. It should also be understood that, depending on the example, certain acts or events of any of the processes or methods described herein may be performed in a different sequence, may be added, merged, or left out altogether (e.g., all described acts or events may not be necessary to carry out the techniques).

Unless otherwise specifically defined herein, all terms are to be given their broadest possible interpretation including meanings implied from the specification as well as meanings understood by those skilled in the art and/or as defined in dictionaries, treatises, etc. It must also be noted that, as used in the specification and the appended claims, the singular forms “a,” “an” and “the” include plural referents unless otherwise specified, and that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof.

Claims (20)

What is claimed is:

1. A unibody intervertebral implant movable between a contracted position and an expanded position, comprising:

a unitary expandable body extending from a proximal side to a distal side in a longitudinal direction, extending from a first lateral side to a second lateral side in a lateral direction, and extending from a superior side to an inferior side in a vertical direction;

the unitary expandable body being defined by an inferior portion comprising an inferior endplate configured to contact an inferior vertebrae, and a superior portion comprising a superior endplate configured to contact a superior vertebrae, the inferior portion being connected to the superior portion adjacent the distal side of the body at a connection region;

a set screw rotatably supported by a threaded aperture formed within the proximal side of the body and rotatable in a clockwise direction and counterclockwise direction around a rotation axis; and

a plug disposed adjacent to and in contact with the set screw, the plug having a first inclined surface facing the distal side of the body,

wherein:

the superior portion comprises a first inclined ramp disposed on an interior surface thereof and facing the first inclined surface of the plug,

the set screw is movable in the longitudinal direction towards the distal side of the body upon rotation of the set screw along the rotation axis, and

movement of the set screw in the longitudinal direction towards the distal side of the body urges the first inclined surface of the plug against the first inclined ramp thereby moving the body into an expanded position by increasing a vertical distance between the superior portion and inferior portion of the body.

2. The unibody implant ofclaim 1, wherein the connection region is configured to function as a hinge that undergoes an elastic deformation in the expanded position.

3. The unibody implant ofclaim 1, wherein the inferior portion comprises the threaded aperture rotatably supporting the set screw and a plug cavity housing the plug.

4. The unibody implant ofclaim 1, wherein the first inclined surface is a planar surface.

5. The unibody implant ofclaim 1, wherein:

the inferior portion is connected to the superior portion at the distal side and the distal side is elastically deformable,

the first lateral side comprises a first slit formed as a first discontinuity between the inferior portion and the superior portion, and

the second lateral side comprises a second slit formed as a second discontinuity between the inferior portion and the superior portion.

6. The unibody implant ofclaim 5, wherein the first discontinuity comprises a first generally teardrop-shaped cutout proximate the distal side and the second discontinuity comprises a second generally teardrop-shaped cutout proximate the distal side.

7. The unibody implant ofclaim 5, wherein:

the proximal side comprises a third slit formed as a third discontinuity between the inferior portion and the superior portion,

the first slit intersects with the third slit adjacent an inferior surface of the inferior portion, and

the second slit intersects with the third slit adjacent a superior surface of the superior portion.

8. The unibody implant ofclaim 7, wherein the first slit and second slit comprise an undulating pattern, respectively.

9. The unibody implant ofclaim 1, wherein:

the inferior portion is connected to the superior portion at the distal side and the distal side is elastically deformable,

the first lateral side comprises a first slit formed as a first discontinuity between the inferior portion and the superior portion,

the second lateral side comprises a second slit formed as a second discontinuity between the inferior portion and the superior portion,

the proximal side comprises a third slit formed as a third discontinuity between the inferior portion and the superior portion,

the first slit connects to the third slit adjacent an inferior surface of the inferior portion, and

the second slit connects to the third slit adjacent a superior surface of the superior portion.

10. The unibody implant ofclaim 1, wherein:

the plug comprises a stabilizing element extending from an upper portion of the plug towards the proximal side of the body, and

an underside of the stabilizing element directly contacts an upper surface of the inferior portion.

11. The unibody implant ofclaim 10, wherein in an expanded position compressive forces applied to the superior portion are transferred to the inferior portion via the first inclined surface of the plug and the stabilizing element of the plug.

12. The unibody implant ofclaim 10, wherein: the inferior portion comprises the threaded aperture rotatably supporting the set screw, an upper portion of the threaded aperture is discontinuous, and the plug extends through the upper portion of the threaded aperture.

13. The unibody implant ofclaim 12, wherein the stabilizing element comprises a planar surface that extends over the upper portion of the threaded aperture.

14. The unibody implant ofclaim 1, wherein the inferior portion comprises a first bone screw aperture extending from a first vertical surface of the inferior portion and through a bottom surface of the inferior portion, the first bone screw aperture defining a first bone screw trajectory projecting towards the distal side that is inclined with respect to the bottom surface of the inferior portion.

15. The unibody implant ofclaim 14, wherein the superior portion comprises a second bone screw aperture extending from a second vertical surface of the superior portion and through a top surface of the superior portion, the second bone screw aperture defining a second bone screw trajectory projecting towards the distal side that is inclined with respect to the top surface of the superior portion.

16. The unibody implant ofclaim 1, wherein the set screw comprises a first hollow interior and the plug comprises a second hollow interior.

17. The unibody implant ofclaim 1, wherein the plug comprises a cylindrical portion having a center point and the rotation axis of the set screw is coaxially aligned with the center point of the plug.

18. The unibody implant ofclaim 1, wherein the plug comprises a cylindrical portion having a hollow center and the rotation axis of the set screw is coaxially aligned with the hollow center of the plug.

19. A method for expanding a unibody implant, comprising:

providing a unibody implant movable between a contracted position and an expanded position, comprising:

a unitary expandable body extending from a proximal side to a distal side in a longitudinal direction, extending from a first lateral side to a second lateral side in a lateral direction, and extending from a superior side to an inferior side in a vertical direction;

the unitary expandable body being defined by an inferior portion comprising an inferior endplate configured to contact an inferior vertebrae and a superior portion comprising a superior endplate configured to contact a superior vertebrae, the inferior portion being connected to the superior portion adjacent the distal side of the body at a connection region;

a set screw rotatably supported by a threaded aperture formed within the proximal side of the body and rotatable in a clockwise direction and counterclockwise direction around a rotation axis; and

a plug disposed adjacent to and in contact with the set screw, the plug having a first inclined surface facing the distal side of the body,

wherein:

the superior portion comprises a first inclined ramp disposed on an interior surface thereof and facing the first inclined surface of the plug,

the set screw is movable in the longitudinal direction towards the distal side of the body upon rotation of the set screw along the rotation axis,

movement of the set screw in the longitudinal direction towards the distal side of the body urges the first inclined surface of the plug against the first inclined ramp thereby increasing a vertical distance of the body between the superior portion and inferior portion of the body, and

rotating the set screw such that it linearly translates from the proximal side towards the distal side of the body;

pushing the plug, by the set screw, towards the distal side of the body; and

urging, by the plug, the first inclined ramp of the superior portion up and away from the inferior portion such that the connection region undergoes an elastic deformation and the unibody implant moves from the contracted position to the expanded position.

20. The method ofclaim 19, comprising:

maintaining the unibody implant in the expanded position; and

transferring compressive forces of adjacent vertebrae between the superior portion and inferior portion via the first inclined ramp of the superior portion through the first inclined surface of the plug and a stabilizing feature of the plug that directly contacts an upper surface of the inferior portion.

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